Dark-green-black dye.



UNITED STATES PATENT oFFIcE..-

SCHIRMACHER AND RICHARD LEOPOLD, OF HClCHST-ON-THEJlL-ilhi; GERMANY, ASSIGN- OBS T FARBWERKE'VORM, MEISTER LUCIUS & BRUNING, OF HocHsT-oN-rHE MAIN.

GERMANY, A CORPORATION or GERMANY 'DARK-GREEN-BLACK Specification of Letters Patent.

Pat'e'nte'd March 10, 1908.

Application filed February 20, 1907. Serial No. 358,419.

To all whom it'may concern;

and residing at. Hochst-on-the-Main, Ger- -many, have invented certain new and useful Improvements in Dark-GreenBl ack Dyes,

of which the following is a specification.

This invention relates to new vatdyestuffs, the Constitution of which corresponds to the formula wherein R means ethyl and methyl.

" lhe new dyestufis may be obtained by oxidizing -alkylthio oxythionaphthene carbox lie acids (RS :S :C 5 :2 :1) obtained from l 5-a lthiophenvlthioglycollic-ortho-carboxylic acids (RS :SCI-LCOOHzCOOH 5 :2 :1) by I heating with alkali. They'are black powders,

insoluble in water, soluble in hot alcohol, benzene, glacial acetic acid and chloroform with a violet color, in concentrated sulfuric acid with a blue-green color. \Vith alkaline hydrosulfite they yield yellow colored vats Q dyeing wool and cotton black-green shades.

' tion of nitro en having ceased, 30 parts of caustic .sodaye of 40 B. specific gravity and a solutionof 15 parts of sodium chloracetate are added and the whole is heated to 100 C. for about 3 hours. From the cold solution the 5-acetaminophenylthioglycollic-ortho-carboxylic acid is precipitated by adding mineral acids. It is a feebly colored crystalline powder soluble in hot water and crystallizing therefrom when cold.

I Hydrolysis is effected by dissolving 26 parts of 5-acetaminoplhenylthioglycollicortho-carboxylic acid wit 40 parts of caustic soda-lye of 40 B. specific gravity under addition of the double volume ofwater and by heating to boil, till a testportion'of the solution with hydrochloric acid -no longer gives any precipitate of the unchanged acetyl compound. After acidifying 20 parts of hydrochloric acid of 20. B. specific gravity are added in the cold and diazotized by adding 6.9 parts of nitrite. The diazo solution thus obtained is run at 2025 C. into a solution of parts of sodium carbonate and 18 parts of potassium Xanthogenate, When the evolution of the nitrogen has ceased the 5-xan'tl1ogenate derivative of the phenylthioglycollic-ortho-c-arboxylic acid of the formula (C H OCSQC I L (SCH COOH COOH) is precipitated by adding a mineral acid. The product of reaction separating in form of a soft mass soon solidifies. To transform it into the 5-methylthiophenylthioglycollic-ortho-carboxylic acid it is dissolved with 45 parts of caustic soda-lye of 40 Be. specific gravity and 25 parts of sodium methylsulfate in 250 parts of water and boiled for 23 hours under reflux. When cold it is filtered and the 5-methylthiophenylthioglycollic-orthocarboxylic acid is precipitated as a yellowish body by adding mineral acids; recrystallized from water it is a crystalline powder decomposing and melting at 180188. v

To transform into the corresponding 5 methylthio oxythionaphthene carboxylic acid 26 parts of 5-methylthiophenylthioglycollic-ortho-carboxylic acid are introduced into a mixture of 150 parts of caustic soda and 15 parts of water. The whole is heated to 180-190 C. and this temperature is he t for some time. The mass becomes gradually solid and brittle. When cold it is dissolved in water. On addition of mineral acids the 5 methylthio-oxythionaphthene carboxylic acid is recipitated in form of white flakes. If boiled with hydrochloric acid there is ob tained the corresponding 5-methylthio-oxythionaphthene while eliminating carbonic acid. This methylthio-oxythionaphthene carboxylic acid or the aforementioned methylthio-oxythionaphthene are characterized by a yellow nitroso derivative which is resulting from them b the action of nitrous acid. The methyltiiio-oxythionaphthene has the melting point 81-82".

To obtain the dyestufl 2% arts by weight of 5-methylthio-oxythionap thene carboxylic acid are dissolved with 15 parts by weight of caustic soda-lye of 40 B. specific gravity in 1000 parts by weight of water, adding a solution of potassium ferri cyanid at gentle heat, till no further dyestufi is formed. The dyestufl' separates in green-black flakes and may be isolated by filtering and washin with water. It has the properties mentionet l above.

In an analogous manner 5-ethylthio-oxythionaphthene carboxylic acid and a ,dyestuff therefrom is obtained, being very similar to that afore described.

we claim is i As products the vat dyestufi's of the constitution of whichcorres ponds to the formula:

wherein R means ethyl and methy being dark green black owders, insoluble in water and soluble in a cohol, glacial acetic acid, benzene and chloroform with a violet color, in concentrated sulfuric acid with a blue green color with alkaline hydrosulfite they yield yellow colored vats dyeing wool and cotton black-green shades.

In testimony, that we claim the foregoing as our invention, we have signed our names in presence of two subscribing witnesses;

5' KARL SCHIRMACHEIL -RICHARD LEOPOLD.

Witnesses 'JE'AN GRUND, CARL GRUND. 

